1. Field
Embodiments of a binder composition for a rechargeable lithium battery, a method of preparing the same, and an electrode for a rechargeable lithium battery and a rechargeable lithium battery including the same are disclosed.
2. Description of the Related Art
A rechargeable lithium battery includes positive and negative electrodes including a material that can reversibly intercalate/deintercalate lithium ions as positive and negative active materials, respectively; and an organic electrolyte solution or a polymer electrolyte solution provided between the positive and negative electrodes. Herein, the positive and negative electrodes intercalate and deintercalate lithium ions and produce electrical energy through oxidation and reduction reactions.
As for a positive active material for a lithium rechargeable battery, a lithium-transition metal oxide capable of intercalating lithium, such as LiCoO2, LiMn2O4, LiNi1-xCoxO2 (0<x<1), and the like, has been used.
As for a negative active material for a lithium rechargeable battery, various suitable carbon-based materials, such as artificial graphite, natural graphite, and hard carbon capable of intercalating and deintercalating lithium ions, have been used. Achieving a battery having high energy density may call for a negative active material having high theoretical capacity density. Accordingly, Si, Sn, and Ge alloyed with lithium and an oxide thereof and an alloy thereof have drawn attention.
For example, a Si-based negative active material has very high charge capacity and is widely applied to a high-capacity battery. However, the Si-based negative active material may expand by about 300% to about 400% during a charge and discharge cycle, and thus charge and discharge characteristics and cycle-life characteristics of batteries including a Si-based negative active material may be deteriorated.
Accordingly, a binder capable of effectively controlling expansion of the Si-based negative active material has been actively researched. For example, developments for a binder composition capable of effectively controlling expansion of the active material have been actively researched.